<table><tr><th>cid</th><th>first_ord</th><th>first_date</th><th>last_ord</th><th>last_date</th><tr><tr><td>c001</td><td>1011</td><td>2016-01-08</td><td>1025</td><td>2016-04-07</td></tr><tr><td>c002</td><td>1013</td><td>2016-01-13</td><td>1026</td><td>2016-05-20</td></tr><tr><td>c003</td><td>1014</td><td>2016-01-18</td><td>1015</td><td>2016-01-23</td></tr><tr><td>c004</td><td>1021</td><td>2016-02-28</td><td>NULL</td><td>NULL</td></tr><tr><td>c006</td><td>1016</td><td>2016-01-25</td><td>1024</td><td>2016-03-12</td></tr></table>